Many reactions, such as the Prins reaction, wherein olefinic materials are reacted with aldehydes, are conducted in the presence of acidic catalysts. The acidic catalysts are generally selected from materials such as para-toluenesulfonic acid, methane sulfonic acid, H2SO4, H3PO4, HCl and the like. When one of the reactants is a relatively large, hydrophobic molecule and one is a relatively small, hydrophilic molecule, the reaction, catalyzed by these materials, may be slow because of difficulty in securing and maintaining sufficient contact between the reactants.
It has now been found that replacing these commonly used catalysts with higher molecular weight, more oleophilic, sulfonic acids results in reduced processing time and improved conversion of reactants.
In U.S. Pat. No. 3,954,808 the reaction of alkyl phenol with glyoxylic acid is described. Examples are given of the reaction with paratoluene sulfonic acid and with H2SO4 catalysts.
The reaction of alkyl phenols with glyoxylic reactants in the presence of methane sulfonic acid is described in U.S. Pat. No. 5,281,346.
U.S. Pat. No. 6,020,500 describes reactions of olefinic compounds with certain carboxylic reactants, including glyoxylic acid, in the presence of an acidic catalyst. Methane sulfonic acid, paratoluene sulfonic acid, heteropolyacids and mineral acids are illustrated.
The preparation of alkyl glycosides by reaction of aqueous glycoses having a water content of 10-80% by weight with aliphatic primary alcohols having from 5 to 30 carbon atoms in the presence of the acidic form of an anionic surfactant used as an acidic catalyst having emulsifying properties is described in U.S. Pat. No. 5,554,742. The patent does not describe reaction of relatively large hydrophobic molecules with relatively small hydrophilic molecules.
The improvement of a rubber having an unsaturated carbon linkage comprising reacting the rubber with an organic compound having a carboxyl group and an aldehyde group in the presence of an acid catalyst is described in U.S. Pat. No. 4,412,041. Acid catalysts include protonic acids such as H2SO4, nitric acid, chlorosulfonic acid, p-toluenesulfonic acid and hydrohalic acids, and Lewis acids.
While the above illustrated catalysts have been moderately successful, the catalysts of the present invention allow intimate mixing of hydrophobic and the hydrophilic media so that side reactions that occur in one phase or the other are minimized.
The process of this invention is useful for preparation of intermediates for further reaction to prepared dispersants and dispersant viscosity improvers for lubricating oil compositions. The products obtained by the process of this invention also find utility as additives for lubricating oil compositions.